Abstract：
:A grazing population dynamics model is proposed where organisms in a grazed population have a fixed life span. The motivating context is that of ruminants grazing grass-dominant pasture. The model takes the form of a differential-delay equation in which the rate of loss of pasture due to senescence at some time depends on the rate at which leaves are reaching maturity at that time. Comparisons are made with data from a continuous grazing experiment due to Bircham and Hodgson (Grass and Forage Science, 38:323-331, 1985), leading to a prediction of 21.9 days for herbage life span. Predictions of herbage utilization are consistent with measured data. The model predicts lower senescence in swards in regrowth than in grazed swards at the same herbage mass. Solutions and equilibria are obtained for the linear form of the model with continuous grazing pressure. Solutions and bounds are obtained for the linear model with intermittent grazing pressure, and its usefulness in modeling grazed pastures is discussed. A delay model is a simple but powerful means of including the concept of fixed herbage life span in grazing modeling. Questions of herbage life span and percentage utilization are naturally contained in the mechanism of a differential-delay model. There are not so well handled by models that treat senescence of herbage empirically.
journal_name
Math Bioscijournal_title
Mathematical biosciencesauthors
Woodward SJ,Wake GCdoi
10.1016/0025-5564(94)90031-0subject
Has Abstractpub_date
1994-05-01 00:00:00pages
37-60issue
1eissn
0025-5564issn
1879-3134pii
0025-5564(94)90031-0journal_volume
121pub_type
杂志文章abstract：:Proteins with multiple binding sites play important roles in cell signaling systems by nucleating protein complexes in which, for example, enzymes and substrates are co-localized. Proteins that specialize in this function are called by a variety names, including adapter, linker and scaffold. Scaffold-mediated nucleati...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2011.06.003
更新日期：2011-08-01 00:00:00
abstract：:A nonlinear mathematical model developed by Chandrasekaran et al. is examined to monitor pharmacokinetic profiles in percutaneous drug absorption and is addressed to several associated problems that could occur in the data analysis of in vitro experiments. The formulation of the model gives rise to a nonlinear partial...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/0025-5564(92)90054-z
更新日期：1992-03-01 00:00:00
abstract：:In this paper, we first propose a prey-predator model with prey-stage structure and diffusion. Then we discuss the following three problems: (1) stability of non-negative constant steady states for the reduced ODE system and the corresponding reaction diffusion system with homogeneous Neumann boundary conditions; (2) ...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2007.08.008
更新日期：2008-04-01 00:00:00
abstract：:The aim of this paper is to develop a minimal model describing events leading to the onset of Parkinson's disease (PD). The model accounts for α-synuclein (α-syn) production in the soma, transport toward the synapse, misfolding, and aggregation. The production and aggregation of polymeric α-syn is simulated using a mi...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2016.05.002
更新日期：2016-08-01 00:00:00
abstract：:In estimating mutation rates using the Luria-Delbrück experimental protocol, it is often assumed that all mutant cells survive the plating procedure to form visible mutant colonies. This assumption of perfect plating efficiency may not hold in certain circumstances, but none of the existing estimation methods that adj...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2008.09.002
更新日期：2008-12-01 00:00:00
abstract：:This paper deals with numerical modeling and simulation of heat transfer in skin tissues using non-linear dual-phase-lag (DPL) bioheat transfer model under periodic heat flux boundary condition. The blood perfusion is assumed temperature-dependent which results in non-linear DPL bioheat transfer model in order to pred...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2017.08.009
更新日期：2017-11-01 00:00:00
abstract：:A biofilm material model and a procedure for numerical integration are developed in this article. They enable calculation of a composite Young's modulus that varies in the biofilm and evolves with deformation. The biofilm-material model makes it possible to introduce a modeling example, produced by the Unified Multi-C...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2014.02.007
更新日期：2014-05-01 00:00:00
abstract：:Interaction of metal or oxide nanoparticles (NPs) with biological soft matter is one of the central phenomena in basic and applied biology-oriented nanoscience. Often, this interaction includes adsorption of suspended proteins on the NP surface, resulting in the formation of the protein corona around NPs. Structurally...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2016.09.018
更新日期：2016-12-01 00:00:00
abstract：:For cDNA array methods that depend on imaging of a radiolabel, we show that bleedover of one spot onto another, due to the gap between the array and the imaging media, can be a major problem. The images can be sharpened, however, using a blind convolution method based on the EM algorithm. The sharpened images look lik...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/s0025-5564(01)00101-8
更新日期：2002-03-01 00:00:00
abstract：:We consider a population with two types of individuals: those who engage in risky sexual behavior (the core) and those who do not (the majority). We are interested in the situation where the majority would not be able to sustain an epidemic without the presence of a core. We show that even if the core is randomly spre...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/s0025-5564(01)00071-2
更新日期：2001-09-01 00:00:00
abstract：:A class of models is considered in which the number of unknown parameters exceeds the number of independent equations that are derived from the input/observation configuration. It is shown that, under certain circumstances, if the number of unknown parameters is sufficiently decreased by setting some of the exit param...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/0025-5564(95)00049-6
更新日期：1996-03-01 00:00:00
abstract：:Many mathematical models in biology and physiology are represented by systems of nonlinear differential equations. In recent years these models have become increasingly complex in order to explain the enormous volume of data now available. A key role of modellers is to determine which components of the model have the ...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2013.12.011
更新日期：2014-02-01 00:00:00
abstract：:Methods of phylogenetic inference use more and more complex models to generate trees from data. However, even simple models and their implications are not fully understood. Here, we investigate the two-state Markov model on a tripod tree, inferring conditions under which a given set of observations gives rise to such ...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2012.03.001
更新日期：2012-05-01 00:00:00
abstract：:The motions of many physical particles as well as living creatures are mediated by random influences or 'noise'. One might expect that over evolutionary time scales internal random processes found in living systems display characteristics that maximize fitness. Here we focus on animal random search strategies [G.M. Vi...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2006.11.014
更新日期：2007-06-01 00:00:00
abstract：:A stochastic model for hospital infection incorporating both direct transmission and indirect transmission via free-living bacteria in the environment is investigated. We examine the long term behavior of the model by calculating a stationary distribution and normal approximation of the distribution. The quasi-station...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2012.10.002
更新日期：2013-01-01 00:00:00
abstract：:Two optimization problems are considered: Harvesting from a structured population with maximal gain subject to the condition of non-extinction, and vaccinating a population with prescribed reduction of the reproduction number of the disease at minimal costs. It is shown that these problems have a similar structure and...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2005.09.001
更新日期：2007-04-01 00:00:00
abstract：:In the present paper, we propose and analyze an eco-epidemiological model with diffusion to study the dynamics of rabbit populations which are consumed by lynx populations. Existence, boundedness, stability and bifurcation analyses of solutions for the proposed rabbit-lynx model are performed. Results show that in the...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2016.08.014
更新日期：2016-11-01 00:00:00
abstract：:Synthetic biology has shown its potential and promising applications in the last decade. However, many synthetic gene networks cannot work properly and maintain their desired behaviors due to intrinsic parameter variations and extrinsic disturbances. In this study, the intrinsic parameter uncertainties and external di...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2010.12.007
更新日期：2011-03-01 00:00:00
abstract：:Colorado River is a unique ecosystem and provides important ecological services such as habitat for fish species as well as water power energy supplies. River management for this ecosystem requires assessment and decision support tools for fish which involves protecting, restoring as well as forecasting of future cond...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2018.02.006
更新日期：2018-04-01 00:00:00
abstract：:The acetone-butanol (AB) fermentation process in the anaerobic endospore-forming Gram-positive bacterium Clostridium acetobutylicum is useful as a producer of biofuels, particularly butanol. Recent work has concentrated on trying to improve the efficiency of the fermentation method, either through changes in the envir...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2012.11.004
更新日期：2013-02-01 00:00:00
abstract：:A key feature of cell migration is how cell movement is affected by cell-cell interactions. Furthermore, many cell migratory processes such as neural crest stem cell migration [Thomas and Erickson, 2008; McLennan et al., 2012] occur on growing domains or in the presence of a chemoattractant. Therefore, it is important...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2015.04.002
更新日期：2015-06-01 00:00:00
abstract：:The combination therapy of antiviral peg-interferon and ribavirin has evolved as one of the better treatments for hepatitis C. In spite of its success in controlling hepatitis C infection, it has also been associated with treatment-related adverse side effects. The most common and life threatening among them is hemoly...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2010.02.005
更新日期：2010-06-01 00:00:00
abstract：:We study spatial stochastic epidemic models called households models. The households models have more than two states at each vertex of a graph in contrast to the contact process. We show that, in the households models on trees, two thresholds of infection rates characterize epidemics. The global critical infection ra...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2008.02.004
更新日期：2008-05-01 00:00:00
abstract：:Reactivity (a.k.a initial growth) is necessary for diffusion driven instability (Turing instability). Using a notion of common Lyapunov function we show that this necessary condition is a special case of a more powerful (i.e. tighter) necessary condition. Specifically, we show that if the linearised reaction matrix an...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2012.04.006
更新日期：2012-09-01 00:00:00
abstract：:A simulation method is presented for the demographic and genetic variation of age structured haploid populations. First, we use matrix analytic methods to derive an equilibrium distribution for the age class sizes conditioned on the total population size. Knowledge of this distribution eliminates the need of a burn-in...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2015.08.003
更新日期：2015-10-01 00:00:00
abstract：:In microarray data analysis, traditional methods that focus on single genes are increasingly replaced by methods that analyse functional units corresponding to biochemical pathways, as these are considered to offer more insight into gene expression and disease associations. However, the development of robust pipelines...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2014.09.005
更新日期：2015-02-01 00:00:00
abstract：:The results of recent experimental and epidemiological studies provide evidence on the connection between carcinogenesis, cancer progression, and aging. Existing models, however, are traditionally focused only on one of these aspects of health deterioration. In this paper, we derive a new model of cancer, which descri...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2008.12.007
更新日期：2009-04-01 00:00:00
abstract：:Metabolic flux analysis using carbon labeling experiments (CLEs) is an important tool in metabolic engineering where the intracellular fluxes have to be computed from the measured extracellular fluxes and the partially measured distribution of 13C labeling within the intracellular metabolite pools. The relation betwee...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/s0025-5564(02)00222-5
更新日期：2003-06-01 00:00:00
abstract：:Traits such as skill at foraging and investment in anti-predator defense may vary among individuals within a species population. This intraspecific variation has implications for community dynamics. The implications of intraspecific variation of a consumer in the intermediate level of a tritrophic food chain are explo...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2013.04.008
更新日期：2013-08-01 00:00:00
abstract：:Pharmacokinetic models are particularly useful to study the underlying and complex physiological mechanisms contributing to clinical differences across patient subgroups or special populations. Unfortunately, the inherent variability of biological systems and knowledge gaps in physiological data limit confidence in mo...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2018.12.011
更新日期：2019-02-01 00:00:00
